How to Do the Norwegian 4×4 Workout (and Is It Worth the Hype)
People who have a high VO2max (one measure of cardio fitness) tend to be healthier as they age and can expect to live longer . With that in mind, some longevity influencers are praising the Norwegian 4×4 workout, which aims to improve your VO2max. So how do you do this? And is it really a miracle cure for fitness and longevity? Let’s get to it.
What kind of training is Norwegian 4×4?
I’ll break it down step by step below, but essentially it’s a cardio workout (traditionally done while running) done in four-minute intervals. You do four of these tough four-minute intervals, hence the name 4×4. There is also a warm-up at the beginning of the workout, a cool-down at the end, and a three-minute rest period between each interval.
If you’re a runner, you’ll recognize this as classic VO2max interval training. (Typically, VO2max intervals are done for three to five minutes, with recovery times similar to or slightly less than work time.) Can’t I just do any old VO2max interval training? You may be asking. Yes you can.
The Norwegian 4×4 workout is a good example of VO2max interval training, but it’s not the only one. Also, VO2 max tempo-focused intervals like this aren’t the only way to improve your VO2max . So 4×4 isn’t anything unique or special, it’s just a simple protocol that’s easy to remember and has been tested on a wide variety of people, including older adults with heart disease.
What benefits can I expect from Norwegian 4×4 training?
After doing this workout regularly (say, twice a week) for a few weeks or months, you can expect an improvement in your cardio fitness, including metrics like “cardio fitness” or “VO2max” readings on your smartwatch. If you enjoy racing, you will notice that you can run them a little faster. It will be more difficult for you to become out of breath if you go on a hike or run around the yard with your children.
Your heart health will likely improve; This exercise pairs perfectly with exercise recommendations for heart health and overall health . Cardio exercise in general, including intervals like these, tends to reduce the risk of heart disease, improve mental health, and more . Again: you can get similar results from other exercises. But 4×4 is one of many good options.
How to do the Norwegian 4×4 workout
4×4 gets its name because you perform four repetitions of four-minute hard intervals. A reputable source on this subject is the Cardio Exercise Research Group at the Norwegian University of Science and Technology (NTNU), which has a video with researcher Anja Bye explaining how it works. For follow-up questions, go to this source and not to podcasters or influencers who try to zone him or change repeats or rest times. If you want to drive a 4×4 SUV, do it right. ( Then , if you like, experiment with it yourself.)
The 4×4 was originally designed for use while running, but the researchers say it can be used with other activities such as “swimming, cycling or skiing.” (Sorry if I don’t have skis ready.) Here’s the protocol:
-
Warm up with a 10-minute moderate-intensity run or brisk walk.
-
First interval : 4 minutes at a hard pace. It may take 1-2 minutes for your heart rate to reach your target (85-95% of your measured maximum heart rate ), and this is normal. If you don’t have a heart rate monitor or don’t know your true maximum, try to work hard enough that you can’t speak in full sentences. Bai says, “The intensity of the last minute should be high, but not so tiring that you can’t complete it.”
-
Recovery: 3 minutes at a moderate pace, jogging or brisk walking. Aim to return to 60-70% of your maximum heart rate.
-
Repeat the intervals until you have completed a total of four of them.
-
Recovery: again 5 minutes of moderate intensity.
Total is 40 minutes:
-
10 minutes warm-up
-
4 minute hard interval
-
3 minutes recovery
-
4 minute hard interval
-
3 minutes recovery
-
4 minute hard interval
-
3 minutes recovery
-
4 minute hard interval
-
5 minutes recovery
Note that recovery between hard intervals takes three minutes, not four. (People tend to remember this part wrong.) Also: Don’t skip your warm-up. This helps get your heart rate up and prepares you for the first interval.
How often should I do the Norwegian 4×4 workout?
NTNU recommends doing this twice a week, plus one longer cardio session during which you only train at a moderate pace. They also recommend that if you exercise four or more times a week, interval training should be half or less of your total training volume. Typically, this will still mean two 4×4 workouts per week, since you’ll be doing two to four workouts of some other type of exercise.
What heart rate zones should I be in?
Trick question! This is not a zone workout. If you use a heart rate monitor, you have numerical goals:
-
85-95% of your testing maximum during the last 2-3 minutes of 4-minute intervals.
-
60-70% during warm-up, recovery and recovery periods.
This 85-95% range includes portions of zones 4 and 5 in most five-zone systems. Your recovery heart rate may again place you in zones 1 and/or 2, depending on how your watch is set. (As I said, zone boundaries vary depending on the device .)
If you are using heart rate as a goal, make sure you know your actual maximum heart rate. Don’t trust your device to figure it out; people are different, and the default formula can easily be off by 10 beats or more . NTNU recommends using a modified 4×4 version to test maximum speed. Start the workout as described above, but when you get to the third interval, do it as hard as you can. The highest number you will see on your watch during this test is the number you should use as the maximum value.
Is this a zone 5 workout?
You’ll probably hit zone 5 at some point during your intervals, so in that sense, yes. But it’s not about getting into zone 5, it’s about following the protocol.
Is this VO2max training?
Yes, this is a pretty classic set of VO2max intervals. However, this is not the only way to improve your VO2max! A good cardio workout comes from training in a variety of ranges, including longer and slower workouts, as well as interval training of varying lengths and intensities. All of this will ultimately improve your VO2max, and better yet, your overall cardio performance.
The idea of VO2max training comes from athletic training, where coaches will consider different aspects of running performance and plan different types of training throughout the season to help their athletes improve their strengths and strengthen their weaknesses. VO2max intervals are part of this process.
In a separate line of thought, researchers studying heart health and longevity have found that VO2max is an aspect of fitness they can test in a consistent and reproducible way. People with better cardio fitness tend to be healthier and live longer, so it’s fair to say that VO2max is related to health. But it’s not because you need to improve your VO2max over other aspects of fitness; this is because becoming more fit will improve your health and your VO2max will increase as a side effect.
Am I doing this right?
I keep seeing posts on Reddit from fans of various biohacking podcasts asking if they did the 4×4 workout correctly. Here’s a checklist:
-
Have you looked up the protocol in its actual source on NTNU? Because some influencers don’t explain it properly or mention it alongside other exercise protocols, and it’s easy to get confused about what the protocol actually is.
-
Did you warm up and cool down? Warming up will set you up for a good first interval. If you start at complete rest, you spend most of the first interval just trying to get your heart pumping.
-
Did you take a three minute rest? Not four minutes. Three minutes. (Not that a four-minute rest would be bad , but it’s not a 4×4 protocol.)
-
Was your heart rate between 85% and 95% of your maximum during the last two minutes of each interval? It takes time to get your heart rate up, but you should hit your target in at least the second half of each interval.
-
Were your levels 70% or less for most of your recovery intervals? It takes time for your heart rate to come down again, but you’re aiming for 70% because that’s the intensity of exercise at which your body can clear lactate most efficiently (to be ready to go back to work).
-
Did you finish your workout feeling like you could have done at least one more round? You’re not trying to completely tire yourself out, just give yourself a challenging workout.
If you do a workout incorrectly, don’t beat yourself up—just write down what you can do better next time. Any type of cardio is good for you and gives you a foundation to build on.